Commutator-brush.



F. W. GARRETT.

GOMMUTATOR BRUSH.

APPLIGATION FILED 11.3, 1906.

Patented Aug. 3, 1909.

IVNVENTOR BY WITNESSES i ATTORNEY UNITED STATES PATENT onnron.

FRANK W. GARRETT, OF PITTSBURG, PENNSYLVANIA, ASSIGNOR TO WESTINGHOUSE ELECTRIC 6: MANUFACTURING COMPANY, A GORPORATIQN OF PENNSYLVANIA.

COMMUTATOR-BRUSH.

Specification of Letters Patent.

Patented Aug. 3, 1909 Application filed January 3', 1906. Serial no, 294,420.

To all whom it may concern:

Be it known that I, FRANK W. GARRETT, a citizen of the United States, and a resident of Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Cominutator- Brushes, of which the following is a specification.

My brushes for dynamo-electric machines, and it has for its object to provide novel and im-. proved means for securing flexible conductors thereto.

My invention is especially applicable to alternating, current motors of the commuta-.

tor type/and to other dy11amo-electric machine's in which thin carbon brushes are essential to the most successful operation.

It has been proposed to provide two or more cavities in the outer end of a con1mutator brush to receive split pins or other rcsilient wedges that project fronr the inner face of a cap plate to which a flexible conductor is connected. unless the cavities and the pins are spaced equal distances apart and are parallel, it is diihcult to apply the cap plate and to make the parts interchangeable, and the object of my invention is to so improve-the structure as to obviate these difiiculties. 9

Figure 1 of the'accompanying drawing is a side view of a commutator brush embodying my invention and Figs. 2 and 3 are views of a modification of'a portion of the structure shown in Fig. 1. V

The outer end of a commutator brush 1 formed of carbon or other suitable material is provided with a cavity 2 and one of its oute'r corners is provided with an inclined, slot or saw-cut 3. A split pin 4 or other suitable resilient wedge that is riveted or otherwise secured to a plate 5 i the cavity 2 and, by reason of t it spreading of the prongs of the fork, makes good electrical connection with the cavity walls. order to preventrotation' of the plate 5 upon the pin 4 as anjaxis, a narrow extension 6 at one endof the plate is bent downwardlyinto the slot'3. One end of a flexible conductor 7 whereby the brush may be connected to a holder (not shown), or to any other portion of an electrical circuit, is secured in the upper invention relates to commutator With such a'stm'cture,

roject'sl into end of a, boss 8 that is riveted or otherwise attached to the plate 5.

Instead of roviding the plate with anextension suc as that shown at 6 in Fig. l,

a portion '9 may be partially severed therefrom and bent downwardly into the slot 3, as shown in Figs. 2 and 3, ora suitable projcction may be provided in. any other manner.

It is obvious that with such a structuri- Ir.) difliculty will be experienced in applying the cap plates to the brushes, and it is to be understood that the plates may serve as wearing pieces for the ends of s )ring-prrssml levers with which the brush holders unprovided. Since no portion of the plate prujects laterally beyond. the side faces of the brush, the latter may be freely moved through the holder.

I claim as my invention:

1 The combination with a commutator brush having a cavity and a slot in its outer end, of a'cap plate for the outer end of the brush only, said plate having, a portion that projects into the slot and a resilient stud that projects into the cavity.

2. The combination with a commutator brush having a cavity and a slot in its outer end, of a cap plate the lcn th and width ol which correspond to the width and thickness of the brush, said plate having a portion that is bent inwardly into the slot and'a resilient stud that projects into the cavity 3. The combination Witlra commutator" brush having an end cavity and a slot in one corner, of a cap plate having a port-rm: that pro ects into the slot and a resilient stud that projects into the cavity.

4. A commutator member comprising carbon block having a cavity in its outer end and an inclined slot or groove Tn one of its outer corners, a cap plate ,liiaving its edges flush with the sides of the clock and provided with'a spring stud that projects into the cavity and with a bent portion sealed in said slot or groove. V

In testimony whereof, I have iii-remain subscribed my name this 30th day of l)ucember, 1905.

FRANK XV. (.lAltltlC'F'l. Witnesses M. MAcLAnnN, BIRNEY .HINES. 

